What is chilled semen?

Chilled semen is semen that is freshly collected, extended with a special media and gradually cooled to, and kept at 4-5°C during transit in a special container. The cooling rates which are required are very important and deviations from these results in poor sperm survival. When kept in this way, the sperm cells are nourished and protected and remain fertile for in excess of 2 days although we prefer to use the semen on the same day as collection.

Why use chilled semen?

The main indication for using chilled semen is to inseminate a bitch that is in another province of the country to the stud. Chilled semen is a cheaper alternative to frozen semen. Chilled semen is not suitable for transport from overseas as the time delay may be too long and delays are expected with regulatory papers and arranging flights in time. Chilled semen insemination requires a veterinary surgeon to monitor the oestrous cycle of the bitch in order to determine, one to two days in advance, when the optimal time is for fertilization. This vet determines when the semen should be collected. A veterinary surgeon needs to be available on the stud’s side to collect the semen and process it correctly.

What are the first steps to take if a breeder plans to make use of chilled semen?

The breeders should contact the veterinarian that will be collecting the semen, processing it and sending it to the veterinarian that monitors the cycle of the bitch. It is strongly advised that both the veterinarians involved are familiar with these specialised procedures and remain in close contact at the time of the insemination. It is of VITAL importance that the breeder presents the dog to the involved vet for a preliminary evaluation. This is necessary to establish whether the stud’s semen is of adequate quality to use for chilled semen purposes and whether it is easy to collect a sample from the stud. It should never be assumed that the stud is a suitable donor for chilled semen based solely on the fact that he has produced a litter some months before. Semen of mediocre quality may in some cases result in conception, but this very same semen may not perform well when chilled because of suboptimal quality. It is not fair to the bitch owner to pay for stud fees, costs for chilled semen, transport and monitoring and insemination of the bitch when poor quality semen was used. Bitch owners should insist on such an evaluation in order to avoid disappointment. Failing to do this may also result in planning the entire event and ultimately abandoning the effort because of poor semen. The bitch owner can then run out of time to look for another stud. The evaluation involves semen collection in the presence of a bitch in heat, performing a semen count, evaluate motility and morphology of the semen under a microscope.

Transport of the chilled semen to and from the airport

If at all possible the airport should be Lanseria as there is little traffic and it is close by. If at Lanseria we will fetch and deliver. If Oliver Tambo is required then we advise the client takes care of collection and delivery to the airport or that a courier service is used.

Monitoring of the bitch

The owner of the bitch needs to contact their reproduction vet and inform him/her of their intention to use chilled semen on the bitch. At this stage he can then refer them to a competent vet closest to the stud owner. The owner will then need to present the bitch for monitoring as soon as she comes in season. The heat cycle will be monitored using either vaginoscopy and/or progesterone assays. It is of vital importance that this monitoring process be done correctly. The veterinarian may require daily access to the bitch for up to 9 days. Some owners find this very frustrating but it is important that this process be done correctly according to requirements. The two vets will stay in contact and give prior notice of the date of collection for shipment. This prior notification is usually within 24-48 hours with the intention to collect on the morning of the planned insemination. The aim will be to get the timing accurate enough to do a single insemination, however, some bitches may require a second insemination 24-48 hours later. All this will be communicated with the owner, stud owner and stud’s veterinarian at the time.

What does the owner of the stud do?

Firstly the owners of the stud should establish whether it is possible to collect semen from him and whether his semen is of adequate quality. This examination should preferably be in the week or days ahead of the time that the bitch will be inseminated as collection of semen usually improves semen quality.

As soon as the date for insemination has been established , the owner of the stud and the vet performing the collection will be informed. The semen will then be collected from the stud, ideally using an “in season” bitch as teaser. The semen is then processed and placed in a special container for transport. It must be decided ahead of time how the semen will be delivered to the nearest airport. The most efficient arrangement is for an individual to deliver it to the cargo section, but couriers can also be used. These details should be arranged by the breeders prior to the day of collection. Usually, the bitch owners are able to arrange for collection of the parcel from their airport. If the semen is being collected anywhere away from the major city metropoles, prior note should be taken of flight times from city to city. In some cases, the time of semen collection becomes important, to ensure that the semen makes it onto a flight on time. The package must be delivered to the airport at least an hour before the flight is scheduled to leave. In the cases of major cities, this is not as critical as there are many flights in a day.

The insemination of the bitch

Once the semen has arrived at its destination (which must be the same day that the semen was collected, or at worst, the following day), the semen is inseminated. The insemination can be performed using intra-vaginal insemination, as with fresh semen inseminations. This procedure takes about fifteen minutes. The veterinarian performing the insemination will have to see the bitch for the next few days following the insemination to establish whether another insemination is required. The veterinarian may also decide to inseminate the bitch via trans cervical insemination (TCI) directly into the uterus using an endoscope or surgically implant the semen via a small incision in the abdominal wall. The latter procedure requires anaesthesia and is sometimes frowned upon and indeed in some countries is deemed illegal. Surgical insemination however has the advantage that it may take shorter than a TCI where the operator struggles and during surgical insemination it can be confirmed that all the semen was deposited into the uterus in all cases. Intra uterine insemination either through an endoscope or via small surgical incision is preferred by some specialists.t

Results using chilled semen

The results obtained with chilled semen are less (65-70%) than those of fresh semen (75-85%) provided the bitch and stud exhibit normal fertility. It is important that in the planning of the insemination the veterinarians involved help the breeders with the selection of suitable candidates for this procedure. Clearly a bitch that has not conceived in previous cycles, is not ideal. It is in everyone’s interest that good results are obtained and poor results are minimized by avoiding unsuitable candidates for semen collection and insemination.

Cost estimate of the procedure

The cost for procedures vary depending on practice and area. Therefore breeders wishing to get an estimate should individually contact the vets on the network. (Contact details below)

There are several costs to consider in this procedure. The respective owners must decide who is responsible for which costs. The norm is that the owner of the bitch is responsible for all the costs or that the male owner carries the cost of the initial evaluation of breeding soundness for the stud as suitable donor of semen.

The costs involved are ; Preliminary semen evaluation to establish semen quality and suitability, Semen collection and processing, Cost of transport (Air Cargo), Any courier costs, Cost of the monitoring of the bitch and insemination


Who to contact for chilled semen insemination and planning


Cape Town:

Dr Rachel Shuttleworth rachelshuttleworth@telkomsa.net


 Dr Kurt De Cramer kdcramer@mweb.co.za


Dr Daniella Steckler daniela-steckler@gmx.de

Port Elizabeth

Dr Stephan Ferreira stephan@walmervet.co.za

Clients wishing to use Onderstepoort for chilled semen should contact them directly.